National Utilization and Expenditure Trends of GLP-1 Receptor Agonists and Dual GLP-1/GIP Agonist in Croatia, 2017-2024.

Background and Objectives: GLP-1 receptor agonists (GLP-1 RAs; ATC A10BJ) and dual GLP-1/GIP agonist (ATC A10BX16) have expanded rapidly due to strong evidence in type 2 diabetes, obesity and metabolic dysfunction-associated steatotic liver disease (MASLD). Their high acquisition costs and accelerating uptake make them key drivers of pharmaceutical expenditure. This study quantified national utilization and expenditure trends for antihyperglycemic drugs in Croatia (2017-2024), with a focus on GLP-1 RA and dual GLP-1/GIP agonists. Materials and Methods: Aggregate national data on dispensed medicines, valued at wholesale pharmacy prices, were obtained from HALMED's annual ATC/DDD reports. Utilization was expressed as defined daily doses per 1000 inhabitants per day (DDD/1000/day). We analyzed the total A10 and key subclasses. The dual GLP-1/GIP agonist was only marketed in 2024. Compound annual growth rates (CAGR) were calculated. Results: The total antihyperglycemic utilization increased from 66.9 to 96.8 DDD/1000/day (a 44.7% rise), while the total A10 expenditure increased from EUR 54.2 million to EUR 96.5 million, indicating that expenditure growth outpaced utilization growth. GLP-1 receptor agonist expenditure increased from EUR 5.2 million (2018) to EUR 28.6 million (2024) (CAGR 33.0%), reaching 29.8% of total A10 expenditure in 2024. Expenditure for GLP-1-based agents grew faster than their DDD volume because per-DDD acquisition costs are substantially higher than for SGLT-2 inhibitors. These growth patterns are consistent with trajectories reported in higher-uptake EU health systems, suggesting convergence rather than an outlier position for Croatia. Conclusions: Croatia experienced a rapid shift towards GLP-1 RA-based antihyperglycemic pharmacotherapy, with GLP-1-based therapies exerting a disproportionate budget impact. For payers, these surveillance data support budget forecasting and negotiation of pricing and reimbursement conditions; clinicians can use them to benchmark and optimize evidence-aligned prescribing; and policymakers can apply them to monitor the diffusion and fiscal impact of high-cost therapies. Routine national ATC/DDD analysis, complemented by HZZO claims and primary-care datasets, is essential for guiding future pricing, reimbursement and formulary decisions.